4 For fear of being accused of abuse—physical, verbal, or emotional—some parents shy away from correcting their children. We need not harbour such fears. The word “discipline” as used in the Bible does not imply any kind of abuse or cruelty.
17. What lesson in parental correction is provided at Isaiah 28:26-29?
...Some children respond to just a glance from their parents, and nothing more is needed. Others require repeated reminders, while still others may need persuasion of a stronger kind.
http://m.wol.jw.org/en/wol/d/r1/lp-e/2001722?q=physical+discipline&p=par#h=6
On Discipline:Dr. James Dobson wrote in The Strong-Willed Child (1978): “Corporal punishment in the hands of a loving parent is a teaching tool by which harmful behavior is inhibited.”
On the other hand, in an article adapted from the seventh edition of the popular book Baby and Child Care (1998), Dr. Benjamin Spock said: “Spanking teaches children that the larger, stronger person has the power to get his way, whether or not he is in the right.”
With regard to discipline, the Bible states: “The rod and reproof are what give wisdom.” (Proverbs 29:15) However, not all children need physical punishment.
Proverbs 17:10 tells us: “A rebuke works deeper in one having understanding than striking a stupid one a hundred times.”
http://m.wol.jw.org/en/wol/d/r1/lp-e/2006801?q=physical+discipline&p=par
God-fearing parents recognize that their children are “an inheritance from Jehovah.” (Psalm 127:3) Thus, they look to God’s Word, the Bible, for guidance in rearing them.
For example, Proverbs 13:24 says: “The one holding back his rod is hating his son, but the one loving him is he that does look for him with discipline.”
The Bible’s use of the word “rod” need not be understood to mean only physical punishment;...
http://wol.jw.org/en/wol/d/r1/lp-e/2001925